Trump's strategy up to this point has been to offer the help to local government and accept if they go "wtf no go away we don't want orange man help" and accept that answer. I mean he's following the hard lefts desire for consent, if they don't want the help then they don't get it.
If he did force order the National Guard in without local gov support. You can bet your left buttcheek that all the local govt would be holding press conferences asap to tell the world how they didn't approve any of it, and the protest management that evening is all down to big orange man, effectively letting them just pass on responsibility that should be theirs alone (or shared because they asked for fed help). The way these "leaders" act after the fact tends to be a tell too. all of them tried to blame Trump when shit hit the wall hard, but it doesn't stick because the leaders have the power to unlock emergency forces if need be.
In short, all these situations are bait to try and get Trump to go "aw heck to another round of this, send in the boys". It solves the problem for democrat leaders who don't have to do much of anything to solve the problem, and allows them to come out the next day with their best somber sad speech about cheetos man invading their fair city and how they really *really* wanted more peaceful protesting but white house said no.
